<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <div class="box" data-id="1">盒子</div>
  <!-- 自定义属性 -->
  <!--Html5中推出的专门的data-自定义属性-->
 
</body>
</html>